Rare-earth magnets have been widely used as permanent magnets used for motors and power generators. Typical examples of rare-earth magnets include sintered magnets composed of R—Fe—B-based alloys (R: rare-earth element, Fe: iron, B: boron), such as Nd (neodymium)-Fe—B; and bond magnets. In bond magnets, magnets composed of Sm (samarium)-Fe—N (nitrogen)-based alloys have been investigated as magnets having magnet properties superior to those of magnets composed of Nd—Fe—B-based alloys.
A sintered magnet is produced by compacting an R—Fe—B-based alloy and then sintering the resulting compact. A bond magnet is produced by subjecting a mixture of a binder resin and an alloy powder composed of an R—Fe—B-based alloy or a Sm—Fe—N-based alloy to compacting or injection molding. In particular, for alloy powders used for bond magnets, hydrogenation-disproportionation-desorption-recombination (HDDR) treatment (HD: hydrogenation and disproportionation, DR: dehydrogenation and recombination) is performed in order to increase the coercive force
While sintered magnets have excellent magnet properties because of its high magnetic phase content, sintered magnets have low degrees of flexibility in shape. It is difficult to form a complex shape, for example, a cylindrical shape, a columnar shape, or a pot-like shape (close-end cylindrical shape). In the case of a complex shape, it is necessary to cut a sintered material. Meanwhile, bond magnets have high degree of flexibility in shape. However, bond magnets have inferior magnet properties to those of sintered magnets. PTL 1 discloses a magnet having an increased degree of flexibility in shape and excellent magnet properties, the magnet being produced by pulverizing an alloy powder composed of a Nd—Fe—B-based alloy, compacting the alloy powder to form a green compact (powder compact), and subjecting the green compact to HDDR treatment.